壁かべ一ひと重え

noun

single wall; one wall

Refers to a wall that is only one layer thick, often implying thinness or lack of privacy. Commonly used in expressions like 壁一重隔てて (separated by just a single wall).

• 隣となりの部屋へやとは壁かべ一ひと重え隔へだてただけだ。

  It's separated from the next room by just a single wall.

• 壁かべ一ひと重えのアパートでは、隣となりの音おとがよく聞きこえる。

  In an apartment with single walls, you can often hear the neighbors.